MATADOR MARTÍNEZ , Esteban

In this PhD Thesis, novel catalytic processes and methodologies for the asymmetric functionalization of prochiral substrates (neutral or ionic) employing hydrazones as versatile umpolung reagents have been developed. In general, double H-bond donors organocatalysts based on unnatural amino acids provided good reactivities and suitable chiral...

An efficient, scalable and operationally simple one-pot, 2-step strategy for the nucleophilic formylation of trifluoromethyl ketones is presented. The key step is an unprecedented diaza-carbonyl-ene reaction of formaldehyde tert-butyl hydrazone and trifluoromethyl ketones under solvent-free conditions. This reaction proved to be very fast,...

The asymmetric 1,2-addition of formyl anion equivalents to carbonyl compounds is a powerful synthetic tool that ideally provide access to highly functionalizable a-hydroxy aldehydes in an enantioselective fashion. In this context, the nucleophilic character of formaldehyde hydrazones, together with their remarkable stability as monomeric...

This Minireview summarizes strategies and developments regarding the use of hydrazones as reagents in asymmetric organocatalysis, their distinct roles in nucleophile–electrophile, cycloaddition, and cyclization reactions. The key structural elements governing the reactivity of these reagents in a preferred pathway will be discussed, as well as...

A highly enantio- and diastereoselective thiourea-catalyzed dearomatization of isoquinolines employing N-tert-butylhydrazones as neutral α-azo carbanions and masked acyl anion equivalents has been developed. Experimental and computational data supports the generation of highly ordered complexes wherein the chloride behaves as a template for the...

The nucleophilic addition of formaldehyde tert-butyl hydrazone to fluoromethyl ketones provides a valuable tool for the synthesis of highly functionalized β-hydroxy β-tri- and difluoromethyl diazenes. Excellent reactivities and moderate to good enantioselectivities (up to 90 % ee) were achieved by H-bonding activation exerted by tert-Leucine...

The nucleophilic addition of formaldehyde tert-butylhydrazone to simple aldehydes (a formal hetero-carbonyl–ene reaction) can be performed with good reactivity and excellent enantioselectivity by virtue of the dual hydrogen-bonding activation exerted by amide–squaramide organocatalysts. The resulting hydroxydiazenes (azo alcohols) were isolated...

Catalysts generated by combinations of Pd(TFA)2 and enantiomerically pure pyridine-hydrazone ligands have been applied to the 1,4-addition of arylboronic acids to β-substituted cyclic enones, building all-carbon quaternary stereocenters in high yields and enantioselectivities (up to 93% ee). The developed methodology allows the efficient...